Now that you lay it all out, there is a pretty funny pattern.
If I remember correctly, I think that retina-scorching Key Lime iBook appeared on the
third generation (or revision?) for that model...
I guess they have a big hit with the first thing. Then build on that for the second-generation version. After that, they get bored and start to believe their hype and decide to, on the third-generation, to "do something different" and "blow everyone away".
On more than a few occasions, however, they've laid a giant iTurd. Or a WTF?! Extreme.
